Simultaneous assessment of chemical and biological contaminants in settled house dust

BACKGROUND AND AIM Settled house dust (SHD) is a reservoir for various contaminants, including endocrine-disrupting chemicals (EDCs), trace metals, and house dust mite allergens. This study aimed to characterize various chemical and biological contaminants in SHD and identify determinants of the indoor contaminants. METHODS In total, 106 SHD samples were collected from 106 houses in Seoul and Gyeonggi Province, Korea in 2021. Thirty of the 106 houses were recruited for collecting bedding dust samples. All participants completed a questionnaire comprised of housing and lifestyle-related factors. Samples were analyzed for 18 organophosphate flame retardants (OPFRs), 16 phthalates, five alternative plasticizers (APs), seven trace metals, and two house dust mite allergens (Dermatophagoides farinae type 1 [Der f1] and Dermatophagoides pteronyssinus type 1 [Der p1]). A multiple regression analysis was conducted to identify the determinants governing the concentrations and profiles of various contaminants. RESULTS OPFRs, phthalates, APs, and trace metals were detected in all SHD samples, indicating ubiquitous contamination in indoor environments. Among the three EDC groups, APs were detected most frequently with the highest concentrations, followed by phthalates and OPFRs. Der f1 was detected in all bedding dust samples with significantly higher levels than Der p1. The concentrations of OPFRs, plasticizers, and trace metals in SHD were significantly associated with the type and number of electronic appliances and combustion activities. Der f1 was significantly associated with the number of occupants and water penetration. Ventilation, vacuum cleaning, and wet cleaning or dry mopping significantly reduced the levels of most contaminants in SHD. CONCLUSIONS As residents are persistently exposed to a wide array of pollutants, comprehensive and adequate measures are required to prevent potential exposures. KEYWORDS Settled house dust; OPFR; Plasticizer; Alternative plasticizer; House dust mite allergens